People donating to causes on Givealittle will have the opportunity to cover the newly introduced 5 per cent fee.
The Spark Foundation announced yesterday a 5 per cent levy on donations will be introduced from September 1 to cover Givealittle's growing costs.
Spark Foundation general manager Lynne Le Gros told Newstalk ZB's Mike Hosking Breakfast that the fee won't cover the full cost of maintaining the platform.
"When we first bought [Givealittle] it was doing just over half a million dollars a year and now we're doing more than that a month," she said.
"We want Givealittle to continue running into the future."
In the latest financial year Kiwis gave $22 million to good causes on the site. Le Gros said the running costs of the site is 8 per cent and has until now been totally covered by the Spark Foundation.
From September, people donating to causes on Givealittle will be asked whether they would donate a bit more to cover the fee.
"Those who are donating will have the opportunity to cover those fees," Le Gros said.
The news about the new levy left those raising funds worried about missing out on money.
Aucklander Sanaz Truter is raising funds to treat son Arian's inoperable and highly aggressive brain tumour, known as diffuse intrinsic pontine glioma. More than 1000 people have contributed about $77,000 to the family, who are saving it while they mount a worldwide search for the best care available.
"That's going to really hurt us," Truter said of the levy. "That's money we're saving up to take Arian overseas for his treatment. That's like 5 per cent less each donation."
Givealittle's biggest campaign raised more than $2m to buy Awaroa Inlet Beach in the Abel Tasman National Park.
In the past year, the Spark Foundation gave $1.7m to Givealittle, but that will likely drop to between $500,000 and $1m this financial year.